The invention relates to a known process for applying a perm or water wave to previously permed or water-waved hair using rollers, the roller members of which, being adjacent on both sides to a center, flexible longitudinal section capable of remaining in a respective bent position, each have an outer longitudinal section, with each one hair strand being rolled onto the roller member starting with the tips of the hair, the roller member being then securely fixed against rotation relative to adjacent rollers and/or the head, and a perm or water-wave liquid being thereafter applied onto the rolled-up hair. The invention relates furthermore to a roller, which is supposed to be particularly suited to carry out this process. The invention includes an improvement to a conventional roller for perm or waterwaves having a roller member preferably provided with openings, onto the outer surface of which roller member a strand of hair can be rolled up, and having a fixing element engaging the roller member, with which fixing element the roller member with the rolled up strand of hair can be securely fixed against rotation relative to adjacent rollers and/or the head.
In one type of roller for perms or water waves, the roller member as a whole is made of a substantially rigid material, in most cases a plastic. After strands of hair divided from the remaining hair have been rolled up to the hairline onto the outer surface of the roller member by rotating the roller member about its axis, the roller member with the rolled up hair strand must be fixed against unrolling. Various types of fixing elements exist for this purpose. In the case of one known perm or water-wave roller (German Patent No. 25 01 935), two flanges arranged at an axial distance from one another and having the same axial thickness are provided at one or both ends of the roller member and an annular groove is provided between both flanges, the width of the groove being slightly less than the thickness of the flange. To fix the roller, one flange of the adjacent roller is pressed in the groove with a clamping action.
The roller member has in other known rollers for creating perms and water waves latticed openings. A needle is used as the fixing element. After one strand of hair has been rolled up onto the roller member, the needle is placed through the rolled-up strand of hair and the openings in the roller member. It can then in addition also be placed into the openings of an already fixed adjacent roller or it can be supported with its end on the head.
Furthermore, rollers are also known which have on one or both ends a holding lever rotatable about the longitudinal axis of the roller member, with a spring-biased ratchet being provided between the holding lever and roller member. After the strand of hair has been rolled up onto the roller member, the holding lever is supported on the head and the spring-biased ratchet prevents the roller from unrolling.
The roller member of a different type of roller includes a center wire core and a flexible member of a viscoelastic plastic surrounding the wire core (German Patent No. 35 39 803 and German Offelengungscchrift No. 32 34 672). The strand of hair in this type of roller is with a straight roller member rolled onto a portion of the roller member such that another portion remains free. When the rolling up to the hair-line is done, the hair-free portion of the roller member is bent and the bent portion is then supported on the head or on an adjacent roller. The center wire core keeps the bent portion in the bent position.
The portion of the roller member which carries the rolled-up strand of hair rests in all of these rollers flat on the head. This has the result that, when perm or water-wave liquid is applied, the entire rolled-up strand of hair is soaked with the liquid from the tips of the hair to the hairline. This is by all means correct for hair which has not been previously treated with a perm or water wave. However, in the case of hair which has already had one or more perm or water-wave treatments, the structure of the hair is damaged at the tips of the hair and in the center portions of the hair by the repeated treatment with a perm or water-wave liquid. In contrast, no damage to the structure of the hair occurs at the hairline, where in the meantime smooth new hair sections have grown, because the newly grown hair sections have previously not been treated with a perm or water-wave liquid. The damage to the structure of the hair is evidenced by the hair loosing its shine at the tips and in the center area, becoming frizzy, and not forming pretty curls.
A basic purpose of the invention is to provide a process for applying a perm or water wave to previously permed or water waved hair of the above-mentioned type, which process substantially avoids damage to the hair structure of the previously permed or water-waved hair even during repeated perm or water-wave treatment and can thereby be carried out easily. A further purpose of the invention is to provide a roller which is particularly suited to carry out this process.